Method and apparatus for digital video latency reduction by real-time warping

ABSTRACT

In one aspect, video latency reduction by real-time warping is described. In one aspect, an original geometric image model of a digital video frame is adjusted according to a video frame latency, to form an adjusted geometric image model. A geometric image model may represent a field of view from a remote camera used to capture the digital video frame. The adjusted geometric image model may be overlaid onto the original geometric image model to capture a warped image. In one aspect the warped image is re-projected according to the adjusted geometric image model to form a re-projected image. The re-projected image may then be displayed to approximate a real-time field of view from a camera used to capture the digital video frame. In one aspect, an attitude and runway alignment of an unmanned aerial vehicle may be controlled using a displayed, re-projected image. Other aspects are described and claimed.

FIELD

An aspect of the present disclosure relates to the field of digitalvideo, and more particularly, to digital video latency reduction of areceived digital video frame captured by a remote camera.

BACKGROUND

Digital video is popular due to its high quality, ease of transmission,and encryption capability. Unfortunately, digital video requirescompression to retain reasonable bandwidth. This generally createsseveral video frames of latency, adding as much as 200-400 milliseconds(ms) of delay. In other words, the received digital video is notrepresentative of a scene in real-time due to the latency caused by thecompression. Highly interactive tasks, such as remote control tasksrequire low latency. Remote control tasks require reacting to displayedimages with precision, which varies in difficulty depending on themagnitude of the latency. Some current methods for reducing videolatency focus on reducing the actual latency of a video stream. Othertechniques provide completely synthetic views.

SUMMARY

One aspect of the subject disclosure describes a method for digitalvideo latency reduction of a received digital video frame captured by aremote camera. In one aspect, an image model of the received digitalvideo frame is adjusted according to an approximate field of view fromthe remote camera at a time the digital video frame is received to forman adjusted image model. In one aspect, the adjusted image model may beoverlaid onto the original image model of the received digital videoframe to capture a warped image. In one aspect, the warped image isre-projected according to the adjusted image model to form are-projected image. The re-projected image may then be displayed toapproximate a real-time field of view from the remote camera used tocapture the digital video frame. In one aspect, an attitude and runwayalignment of an unmanned aerial vehicle may be controlled using adisplayed, re-projected image having an on-board, remote camera.

It is understood that other configurations of the subject technologywill become readily apparent to those skilled in the art from thefollowing detailed description, wherein various configurations of thesubject technology are shown and described by way of illustration. Aswill be realized, the subject technology is capable of other anddifferent configurations and its several details are capable ofmodification in various other respects, all without departing from thescope of the subject technology. Accordingly, the drawings and detaileddescription are to be regarded as illustrative in nature and not asrestrictive.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram illustrating a computer navigation systemaccording to one aspect of the subject disclosure.

FIG. 2 is a diagram illustrating a flow chart for video latencyreduction by real-time warping according to one aspect of the subjectdisclosure.

FIG. 3 is a diagram illustrating a reduced control loop latencyaccording to one aspect of the subject disclosure.

FIG. 4 is a diagram illustrating an example of a camera geometry andfield of view at a digital video frame capture time according to oneaspect of the subject disclosure.

FIG. 5 is a diagram illustrating an example of a camera geometry andfield of view at a digital video frame receive time according to oneaspect of the subject disclosure.

FIG. 6 is a diagram illustrating an example of an original geometricimage model of a digital video frame at a frame capture time accordingto one aspect of the subject disclosure.

FIG. 7 is a diagram illustrating an example of an adjusted geometricimage model overlaid onto the original geometric image model of FIG. 6to capture a warped image according to one aspect of the subjectdisclosure.

FIG. 8 is a diagram illustrating an example of the warped image of FIG.7, re-projected according to the adjusted geometric image model to forma re-projected image according to one aspect of the subject disclosure.

FIG. 9 is a diagram illustrating an example of a camera geometry andfield of view at a digital video frame capture time, including a groundplane, according to one aspect of the subject disclosure.

FIG. 10 is a diagram illustrating an example of a camera geometry andfield of view at a digital video frame receive time, including a groundplane, according to one aspect of the subject disclosure.

FIG. 11 is a diagram illustrating an example of an original geometricimage model of a digital video frame at a frame capture time, includinga ground plane, according to one aspect of the subject disclosure.

FIG. 12 is a diagram illustrating an example of an adjusted geometricimage model overlaid onto the original geometric image model to capturea warped image according to one aspect of the subject disclosure.

FIG. 13 is a diagram illustrating an example of the warped image of FIG.12, re-projected according to the adjusted geometric image model to forma re-projected image according to one aspect of the subject disclosure.

DETAILED DESCRIPTION

The detailed description set forth below is intended as a description ofvarious configurations of the subject technology and is not intended torepresent the only configurations in which the subject technology may bepracticed. The appended drawings are incorporated herein and constitutea part of the detailed description. The detailed description includesspecific details for the purpose of providing a thorough understandingof the subject technology. However, it will be apparent to those skilledin the art that the subject technology may be practiced without thesespecific details. In some instances, well-known structures andcomponents are shown in block diagram form in order to avoid obscuringthe concepts of the subject technology. Like components are labeled withidentical element numbers for ease of understanding.

Digital video is popular due to its high quality, ease of transmission,and encryption capability. Unfortunately, digital video requirescompression to retain reasonable bandwidth. For example, if digitalvideo is encoded using motion picture experts group (MPEG) technology,the latency required to decode and display the video is in the range of200-400 milliseconds (ms). In other words, the received digital video isnot representative of a scene in real-time due to the latency caused bythe compression. This digital video latency is commonly experienced byviewers of digital television who do not notice that the contentdisplayed on their screen does not represent a real-time view for liveevents.

While digital video latency may be acceptable to viewers of digitaltelevision, digital video latency is unacceptable for highly interactivetasks, such as remote control tasks. Remote control tasks requirereacting to displayed images with precision, which varies in difficultydepending on the magnitude of the digital video latency. One example ofa remote control task is the remote control of a vehicle, such as aremotely piloted unmanned aerial vehicle (UAV). Unfortunately, digitalvideo latency prohibits the viewing of changes to a scene in real-timesince changes may occur between the time a scene is captured and a timeat which the scene is displayed at a remote location. The total latencyfor the remote control of a vehicle may depend on properties such as thevehicle response, a radio communication link, and the digital videolatency. A total latency in excess of, for example, 200 ms may causepilot induced oscillations because a display of the digital video framesfrom an on-board camera does not reflect the commands issued to thevehicle, which causes the pilot to issue additional commands, resultingin a loss of control.

According to various aspects of the subject disclosure, digital videolatency reduction by real-time warping is described. In one aspect, eachframe of digital video is re-projected (warped) to approximate ageometry of a future video frame in real-time. In one aspect, a camerageometry for each digital video frame captured by the camera is recordedaccording to a location of the camera at a digital video frame capturetime. Subsequently, an estimate is made of an actual, current camerageometry at a time a digital video frame is received. In one aspect, adifference between the recorded geometry and the current camera geometry(location) is used to re-project or warp the video image to correct forthe difference in the form of a re-projected image. When there-projected image is displayed, the content of the original image doesnot represent a real-time image due to the above-mentioned delay inreceiving the image. The re-projected image, although based on anon-real-time image, will approximate a real-time field of view from thecamera at the video frame receive time. In one aspect of the subjectdisclosure, a current camera geometry may be provided by sensors, suchas an inertial navigation system, or can be estimated from the sceneitself.

As described herein, digital video latency may refer to a time delaybetween a digital video frame capture time and a time at which the videoframe is displayed, which may be in the range of 100 to 200 milliseconds(ms). As further described herein, real-time warping may refer to theremapping of an original geometric image model of digital video frameaccording to an adjusted geometric image model representing anapproximate real-time camera location to approximate a geometry of afuture video frame in real-time. As further described herein, ageometric image model (image model) may refer to an intersection betweena camera field of view and a plane perpendicular to a camera focal planeat a predetermined distance in front of the camera, such that anoriginal geometric image model (original image model) may refer to afield of view from a remote camera used to capture the digital videoframe at a time that the digital video frame is captured, and anadjusted geometric image model (adjusted image model) may refer to afield of view from the remote camera at a time a digital video frame isreceived.

FIG. 1 illustrates a computer navigation system 100 in accordance withthe disclosed aspects. System 100 is operable to access and receivedigital video frames 162 and to access and receive vehicle (camera)location information 164. System 100 may comprise a computer platform110 having a memory 130 operable to store data, logic, and applicationsexecutable by a processor 120. A user may interact with system 100 andits resident applications through one or more user interfaces 102, whichmay include one or more input devices 104 and one or more output devices106. Additionally, system 100 may exchange communications with externaldevices 310/340 (FIG. 3) and/or networks through a communications module114.

Computer platform 110 is operable to transmit data across a network, andis operable to receive and execute routines and applications and displaydata generated within system 100 or received from any network device orother computer device connected to the network or connected to system100. Computer platform 130 may be embodied in, for example, one or anycombination of hardware, firmware, software, data and executableinstructions.

Memory 130 may comprise one or any combination of volatile andnonvolatile memory, such as read-only and/or random-access memory (RAMand ROM), EPROM, EEPROM, flash cards, flash memory cells, an electronicfile system, and any memory common to computer platforms. Further,memory 130 may include one or more of any secondary or tertiary storagedevice, such as magnetic media, optical media, tape, or soft or harddisk, including removable memory mechanisms.

Further, processor 120 may be one or more of an application-specificintegrated circuit (“ASIC”), a chipset, a processor, a logic circuit,and any other data processing device. In some aspects, processor 120, oranother processor such as an ASIC, may execute an applicationprogramming interface (API) layer 112 that interfaces with any residentprograms stored in memory 130 of system 100. API 112 may be a runtimeenvironment executing on system 100. In one aspect, API 112, incombination with navigation menu 144, may be used control the operationof a remote vehicle.

Additionally, processor 120 may include graphic processing unit (GPU)122 embodied in hardware, firmware, software, data, executableinstructions and combinations thereof, which enable video latencyreduction according to one embodiment. For example, GPU 122 incombination with video re-projection logic 142 of latency reductionmodule 140 may enable video latency reduction by real-time warping.

Further, communications module 114 may be embodied in hardware,firmware, software, data, executable instructions and combinationsthereof, and is operable to enable communications among the variouswireless data links. For example, communication module 114 may includethe requisite hardware, firmware, software, data, executableinstructions and combinations thereof, including transmit and receivechain components for establishing a wireless communication connection.

Further, for example, communication module 114 is operable to receive aplurality of digital video frames 162 and the associated respectivecamera locations 164 at a video frame capture time, and forwards them toreal-time image selector 150 or provides image selector 150 with accessto the data. Similarly, for example, communication module 114 isoperable to receive navigation data regarding a camera location 164 at avideo frame receive time and either forwards them to image selector 150or provides image selector 150 with access to the data. Subsequently,for example, communications module 114 is operable to forward digitalvideo content to other device components for further processing.

Additionally, one or more input devices 104 for generating inputs intosystem 100, and one or more output devices 106 for generatinginformation for consumption by the user of the system are provided. Forexample, input device 104 may include a mechanism such as a key orkeyboard, a navigation mechanism (e.g. a joy stick), a mouse, atouch-screen display, a microphone in association with a voicerecognition module, etc. In certain aspects, input device 104 providesan interface for receiving user input, such as to activate or interactwith an application or module on a remote vehicle. Further, for example,output device 102 may include a display, an audio speaker, a hapticfeedback mechanism, etc. Further, user interface 102 may comprise one orany combination of input devices 104 and/or output devices 106.

FIG. 2 is a diagram illustrating a flowchart 200 for real time videowarping, according to one aspect of the present disclosure. At processblock 202, a camera location is recorded for each digital video frame ata frame capture time. At process block 204, it is determined whether aframe is received. Once received, at process block 206 an originalgeometric image model of a camera field of view at the frame capturetime is determined. At process block 208, the original geometric imagemodel is modified according to an approximate field of view of thecamera at a video frame receive time. At process block 210, the adjustedgeometric image model is overlaid onto the original geometric imagemodel to capture a warped image. At process block 212, a field of viewof the warped image is reduced to eliminate one or more edges of thewarped image to form a re-projected image. At process block 214 there-projected image is displayed to approximate a real-time field of viewfrom the camera at the video frame receive time.

Referring again to FIG. 1, latency reduction module 140 in combinationwith GPU 122 may be operable to perform the features of FIG. 2.Representatively, latency reduction module 140, may include videore-projection logic 142 and navigation menu 144. In one aspect,navigation menu 144 may be provided to control the operation of avehicle. As shown in FIG. 1, real-time image selector 150, may beresponsible for receiving digital video frames 162 and camera locations164 for storage within storage device 160. In one aspect, a digitalvideo latency may refer to a delay between a time at which a video frameis captured by a camera 310 (FIG. 3) and a time at which the video frameis received at communications module 114.

Referring again to FIG. 1, in response to a received digital video frame162, real-time image selector 150 may determine a camera location 164 atthe time the frame is received, which is later in time than the time atwhich the frame was captured due to video latency. According to thedescribed aspects, original image model 166 may represent a field ofview of the camera at a time that digital video frame was captured. Asfurther shown in FIG. 1, adjusted image model 168 may approximate afield of view of a camera at real-time, which may be a time at which thedigital video frame was received. According to the described aspects,although the received digital video frame 162 is not current (due to thevideo latency), video re-projection logic 142 may re-project digitalvideo frame 162 using the adjusted image model 168 to approximate acurrent real-time view from a camera 310 (FIG. 3).

FIG. 3 is a block diagram illustrating a reduced control loop latency300, according to one aspect of the present disclosure. As shown in FIG.3, input device 104 may represent a joystick or controller forcontrolling a vehicle. Blocks 302-308 represent latency times fordirecting a command from controller 104 to a remote vehicle. As furthershown in FIG. 3, a video frame latency path 330 (332-336) is shown inrelation to a video warping path 320 that includes blocks 322-326. Thetotal latency time provided by video latency path 330 include a total of243 ms. To avoid the latency caused by video latency path 330, a videowarping path 320 is described, which includes a total latency time of 28ms. Representatively, a camera location at a time when a video frame isreceived may be determined using for example, an inertial navigationsystem 340 which may provide a sample vehicle position and attitude,including a roll, pitch, and yaw for an unmanned aerial vehicle (UAV).Alternatively, a global positioning system (GPS) may also be used toprovide a current location of camera 310.

As shown in FIG. 3, the delay required to receive or approximate areal-time location of camera 310 is less than the video frame latencypath 330. By taking advantage of the reduced video frame warping path320, a geometric image model may be used to approximate a currentreal-time location of camera 310. Using this approximate model, anoriginal digital frame image may be remapped according to theapproximated model to provide a warped image, for example as shown inFIGS. 8 and 13.

FIG. 4 is a diagram 400 illustrating a location 402, of camera 310 at avideo frame capture time. Representatively, a horizontal distance 404 toan image plane 410 is shown. Also illustrated is a field of view ofcamera 310, which intersects plane 410 at points a 406 and b 408. FIG. 4is a simplified view of, for example, a frustum view of the camera fieldof view intersection with image plane 410.

FIG. 5 is a diagram 420 illustrating a location 422 of camera 310 at atime at which a digital video frame is received, which may be referredto herein as a real-time location of camera 310. Based on the real-timelocation 422 of camera 310, a frustum view of the intersection betweenthe field of view of camera 310 and image plane 430 is shown based onelements a′ 416 and b′ 418.

FIG. 6 is a block diagram illustrating a frustum view 440 at a videoframe capture time. Representatively, a runway is shown in the distance.In the aspect described in FIG. 6, an attitude of a vehicle isconsidered due to a distance from the runway. As further described withreference to FIGS. 9-13, a ground plane may be included to allow forvehicle takeoffs and landings.

As described herein, frustum view 440 may be referred to as an originalgeometric image model of a digital video frame, which represents a fieldof view of a camera at a time that the digital video frame is captured.Unfortunately, for the reasons described above, by the time the digitalvideo frame represented by FIG. 6 is received by, for example, system100, that digital video frame no longer represents a real-time view fromcamera 310. According to one aspect of the present disclosure, thislatent image may be modified to form a warped image to illustrate areal-time location of camera 310.

FIG. 7 is a diagram, which illustrates the overlaying of an adjustedgeometric image model 450 onto original geometric image model 440.Representatively, the adjusted geometric image model 450 is representedby points a′ 416, b′ 418, c′ 452, and d′ 454. Once the adjustedgeometric image 450 is overlaid onto the original geometric image model440, a warped image may be determined to approximate a real-time cameraview, for example, as shown in FIG. 8.

FIG. 8 represents a re-mapping of an original geometric image accordingto an adjusted geometric image model based on points a′ 416, b′ 418, c′452, and d′ 454. As shown in FIG. 8, warped image 460 is no longeraligned with the mapping based on the adjusted geometric model andincludes various edges (gaps) that are out of alignment with theadjusted model. In one aspect of the present disclosure, a field of viewof the original geometric image model may be larger than a field of viewfor a re-projected image 480. This re-projected image field of view 470is shown such that an image is captured, based on the reduced field ofview, to provide re-projected image 480. As shown in FIG. 8, the latentoriginal image is re-projected to represent a real-time field of viewfrom the camera, which will enable more accurate control of, forexample, a vehicle, including a camera as well as a remote controlapplication.

FIGS. 9-13 represent similar features as described with reference toFIGS. 5-8, however, shown to include a ground plane 514 as introduced inFIG. 9. As illustrated in FIG. 10, a subsequent location 522 of thecamera 310 is captured to provide an adjusted geometric image model. Asshown in FIG. 11, an original geometric image model 540 includes aground plane identified by point numerals 512 (c) and 546 (e), based onoriginal mapping points a 506, b 508, c 542, and d 544. FIG. 13 is adiagram, which illustrates the overlaying of an adjusted geometric imagemodel 550 onto original geometric image model 540. Representatively, theadjusted geometric image model 550 is represented by points a′ 516, b′518, c′ 552, and d′ 554, as well as ground plane points c′ 524 and e′556. Once the adjusted geometric image model 550 is overlaid onto theoriginal geometric image model 540, a warped image may be determined toapproximate a real-time camera view, for example, as shown in FIG. 13.

FIG. 13 represents a re-mapping of an original geometric image model 540according to an adjusted geometric image model 550 based on points a′516, b′ 518, c′ 552, and d′ 554, as well as ground plane points c′ 524and e′ 556. As shown in FIG. 13, warped image 560 is no longer alignedwith the mapping based on the adjusted geometric model 550 and includesvarious edges (gaps) that are out of alignment with the adjusted model.In one aspect of the present disclosure, a field of view of the originalgeometric image model 550 may be larger than a field of view for are-projected image 580. This re-projected image field of view 570 isshown such that an image is captured, based on the reduced field ofview, to provide re-projected image 580. As shown in FIG. 13, the latentoriginal image is re-projected to represents a real-time field of viewfrom the camera, which will enable more accurate control for landing avehicle, including a camera as well as a remote control application.

Aspects of the subject technology bypass the extra latency inherent todigital compression/decompression and delay by using a wireless datalink and an inertial navigation system to provide a low latency datapath for determining a real-time location of a camera included within avehicle. Although received digital video data from a vehicle includingthe camera is still latent, a relative position and attitude indicatedby the digital video data may be corrected to approximate a geometry ofa future video frame in real-time. In some aspects, the subjecttechnology may be applied in radio communication, wirelesscommunication, and electronics. In some aspects, the subject technologymay be applied in non-aerial vehicle control, for example, such asstandard automobiles.

In accordance with various aspects of the subject disclosure, thesubject technology is related to video latency reduction. In someaspects, the subject technology may be used in various markets,including for example and without limitation, remote control tasks basedon a video image that require low latency. For example, the videoreduction latency, according to one aspect, is described for landing aremotely piloted vehicle. The described aspects, however, are notlimited to landing a remotely piloted vehicle, and may be applied to anycontrol task that requires low latency.

It is to be understood that the embodiments described herein may beimplemented by hardware, software, firmware, middleware, microcode, orany combination thereof. When the systems and/or methods are implementedin software, firmware, middleware or microcode, program code or codesegments, they may be stored in a machine-readable medium, such as astorage component. A code segment may represent a procedure, a function,a subprogram, a program, a routine, a subroutine, a module, a softwarepackage, a class, or any combination of instructions, data structures,or program statements. A code segment may be coupled to another codesegment or a hardware circuit by passing and/or receiving information,data, arguments, parameters, or memory contents. Information, arguments,parameters, data, etc. may be passed, forwarded, or transmitted usingany suitable means including memory sharing, message passing, tokenpassing, network transmission, etc.

For a software implementation, the techniques described herein may beimplemented with modules (e.g., procedures, functions, and so on) thatperform the functions described herein. The software codes may be storedin memory units and executed by processors. The memory unit may beimplemented within the processor or external to the processor, in whichcase it can be communicatively coupled to the processor through variousmeans as is known in the art.

Moreover, various aspects or features described herein may beimplemented as a method, apparatus, or article of manufacture usingstandard programming and/or engineering techniques. The term “article ofmanufacture” as used herein is intended to encompass a computer programaccessible from any computer-readable device, carrier, or media. Forexample, computer-readable media can include but are not limited tomagnetic storage devices (e.g., hard disk, floppy disk, magnetic strips,etc.), optical disks (e.g., compact disk (CD), digital versatile disk(DVD), etc.), smart cards, and flash memory devices (e.g., EPROM, card,stick, key drive, etc.). Additionally, various storage media describedherein can represent one or more devices and/or other machine-readablemedia for storing information. The term “machine-readable medium” caninclude, without being limited to, wireless channels and various othermedia capable of storing, containing, and/or carrying instruction(s)and/or data.

It is understood that the specific order or hierarchy of steps in theprocesses disclosed is an illustration of exemplary approaches. Basedupon design preferences, it is understood that the specific order orhierarchy of steps in the processes may be rearranged. Some of the stepsmay be performed simultaneously. The accompanying method claims presentelements of the various steps in a sample order, and are not meant to belimited to the specific order or hierarchy presented.

The previous description is provided to enable any person skilled in theart to practice the various aspects described herein. The previousdescription provides various examples of the subject technology, and thesubject technology is not limited to these examples. Variousmodifications to these aspects will be readily apparent to those skilledin the art, and the generic principles defined herein may be applied toother aspects. Thus, the claims are not intended to be limited to theaspects shown herein, but is to be accorded the full scope consistentwith the language claims, wherein reference to an element in thesingular is not intended to mean “one and only one” unless specificallyso stated, but rather “one or more.” Unless specifically statedotherwise, the term “some” refers to one or more. Pronouns in themasculine (e.g., his) include the feminine and neuter gender (e.g., herand its) and vice versa. Headings and subheadings, if any, are used forconvenience only and do not limit the invention.

A phrase such as an “aspect” does not imply that such aspect isessential to the subject technology or that such aspect applies to allconfigurations of the subject technology. A disclosure relating to anaspect may apply to all configurations, or one or more configurations.An aspect may provide one or more examples. A phrase such as an aspectmay refer to one or more aspects and vice versa. A phrase such as an“embodiment” does not imply that such embodiment is essential to thesubject technology or that such embodiment applies to all configurationsof the subject technology. A disclosure relating to an embodiment mayapply to all embodiments, or one or more embodiments. An embodiment mayprovide one or more examples. A phrase such an embodiment may refer toone or more embodiments and vice versa. A phrase such as a“configuration” does not imply that such configuration is essential tothe subject technology or that such configuration applies to allconfigurations of the subject technology. A disclosure relating to aconfiguration may apply to all configurations, or one or moreconfigurations. A configuration may provide one or more examples. Aphrase such a configuration may refer to one or more configurations andvice versa.

The word “exemplary” is used herein to mean “serving as an example orillustration.” Any aspect or design described herein as “exemplary” isnot necessarily to be construed as preferred or advantageous over otheraspects or designs.

All structural and functional equivalents to the elements of the variousaspects described throughout this disclosure that are known or latercome to be known to those of ordinary skill in the art are expresslyincorporated herein by reference and are intended to be encompassed bythe claims. Moreover, nothing disclosed herein is intended to bededicated to the public regardless of whether such disclosure isexplicitly recited in the claims. No claim element is to be construedunder the provisions of 35 U.S.C. §112, sixth paragraph, unless theelement is expressly recited using the phrase “means for” or, in thecase of a method claim, the element is recited using the phrase “stepfor.” Furthermore, to the extent that the term “include,” “have,” or thelike is used in the description or the claims, such term is intended tobe inclusive in a manner similar to the term “comprise” as “comprise” isinterpreted when employed as a transitional word in a claim.

1. A method for digital video latency reduction of a received digitalvideo frame captured by a remote camera, the method comprising:adjusting an image model of the received digital video frame accordingto an approximate field of view from the remote camera at a time thedigital video frame is received to form an adjusted image model;overlaying the adjusted image model onto the image model of the receiveddigital video frame to capture a warped image; and re-projecting thewarped image according to the adjusted image model to form are-projected image that approximates a real-time field of view from theremote camera used to capture the received digital video frame.
 2. Themethod of claim 1, wherein the remote camera is attached to an unmannedaerial vehicle, the method further comprising: displaying a plurality ofre-projected images based a plurality of received digital video framescaptured by the remote camera on a display at a remote location; andcontrolling an attitude and runway alignment of the unmanned aerialvehicle in response to user commands from viewing the plurality ofdisplayed, re-projected images.
 3. The method of claim 1, furthercomprising: storing a camera attitude for each recorded digital videoframe at a time that each digital video frame is recorded according toreceived navigation data.
 4. The method of claim 3, wherein the cameraattitude for each recorded frame is received over a wireless link. 5.The method of claim 1, wherein overlaying further comprises: mapping thereceived digital video frame onto the adjusted image model to form thewarped video frame; and reducing a field of view of the warped videoframe to eliminate one or more edges of the warped video frame to formthe re-projected image.
 6. The method of claim 1, wherein adjustingfurther comprises: reverse-mapping the received digital video frame todetermine an original geometric image model corresponding to a field ofview of the remote camera at a digital video frame capture time; andmodifying the image model of the received digital video frame toapproximate the real-time field of view from the remote camera at thetime the digital video frame is received to form the adjusted imagemodel.
 7. The method of claim 1, further comprising: rendering, using agraphics processing unit, a composite two-dimensional display of thedigital video frame by applying the video frame to a three-dimensionalgeometry corresponding to a field of view of the remote camera at thetime the video frame is captured to approximate a real-time view from avehicle including the camera.
 8. A non-transitory computer readablemedium having processor-executable software instruction to perform amethod digital video latency reduction of a received digital video framecaptured by a remote camera, comprising: re-mapping the digital videoframe to determine an original geometric image model corresponding to afield of view from the remote camera used to capture the digital videoframe at a digital video frame capture time; modifying the originalgeometric image model according to an approximate field of view from theremote camera at a digital video frame receive time to form an adjustedgeometric image model; overlaying the adjusted geometric image modelonto the original geometric image model to capture a warped image; andreducing a field of view of the warped video frame image to eliminateone or more edges of the warped video frame image to form a re-projectedimage; and displaying the re-projected image to approximate a real-timefield of view from the camera at the video frame receive time.
 9. Thenon-transitory computer readable medium of claim 8, further comprising:maintaining an attitude and runway alignment of an unmanned aerialvehicle using a displayed, re-projected image.
 10. The non-transitorycomputer readable medium of claim 9, wherein reverse-mapping furthercomprises: adjusting an original geometric image model of a digitalvideo frame according to a delay between a video frame receive time avideo frame capture time to form the adjusted geometric image model 11.The non-transitory computer readable medium of claim 8, whereindisplaying further comprises: rendering, using a graphics processingunit, a composite two-dimensional display of the video frame by applyingthe video frame to a three-dimensional geometry corresponding to a fieldof view of the camera at the video frame capture time.
 12. Thenon-transitory computer readable medium of claim 11, further comprising:storing a camera attitude for each recorded frame, at a time that eachframe is recorded, according to received navigation data, wherein thecamera attitude for each recorded frame is received over a wirelesslink.
 13. The non-transitory computer readable medium of claim 8,wherein overlaying further comprises: mapping the video frame onto theadjusted geometric image model to form the warped video frame image. 14.The non-transitory computer readable medium of claim 8, whereinoverlaying further comprises: warping each frame of digital video toapproximate a geometry of a future video frame in real-time.
 15. Asystem for digital video latency reduction of a received digital videoframe captured by a remote camera, comprising: a transceiver configuredto receive the digital video frame and a camera geometry at a digitalvideo frame capture time; a memory operable to store the receiveddigital video frame and the camera geometry; a graphics processing unitoperable to determine an original geometric image model corresponding toa field of view from the remote camera used to capture the digital videoframe, at the digital video frame capture time, to overlay an adjustedgeometric image model onto the original geometric image model to capturea warped image, the adjusted geometric image model corresponding to anapproximate field of view from the remote camera at a digital videoframe receive time, and to reduce a field of view of the warped videoframe to eliminate one or more edges of the warped image to form are-projected image; a display operable to display the re-projected imageto approximate a field of view from the camera used to capture the videoframe according to a location of the camera at the video frame receivetime; and a controller operable to control a vehicle, including theremote camera, according to a re-projected image.
 16. The system ofclaim 15, wherein the graphics processing unit is further operable towarp each frame of digital video to approximate a geometry of a futurevideo frame in real-time.
 17. The system of claim 15, wherein thegraphics processing unit is further operable to re-map the digital videoframe to determine the original geometric image model corresponding to afield of view of the camera at the video frame capture time and tomodify the original geometric image to approximate the real-time fieldof view of the camera at the video frame receive time to form theadjusted geometric image.
 18. The system of claim 15, further comprisingan application programming interface to control an attitude and runwayalignment of an unmanned aerial vehicle using a displayed, re-projectedimage.
 19. The system of claim 15, wherein the vehicle comprises anunmanned aerial vehicle.
 20. The system of claim 19, wherein the vehiclecomprises an inertial navigation system operable to provide a camerageometry for each recorded digital video frame at a time the frame iscaptured.